1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) Sensory Thresholds in Riesling Wine.

Area of Science:

• Oenology and Wine Chemistry
• Sensory Science
• Aroma Compound Analysis

Background:

• 1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) is a key aroma compound.
• TDN imparts characteristic kerosene/petrol notes to Riesling wines.
• Understanding TDN's sensory impact is crucial for wine quality assessment.

Purpose of the Study:

• To determine the sensory thresholds for TDN in Riesling wine.
• To investigate the influence of free sulfur dioxide (SO2) on TDN perception.
• To evaluate the effect of wine serving temperature on TDN aroma recognition.

Main Methods:

• Sensory analysis to establish detection, recognition, and rejection thresholds for TDN.
• Experimental manipulation of free SO2 levels in wine samples.
• Comparative sensory evaluation of TDN aroma at different serving temperatures (11°C vs. room temperature).

Main Results:

• Detection threshold for TDN was approximately 4 µg/L.
• Recognition threshold ranged from 10-12 µg/L, and rejection threshold from 71-82 µg/L.
• Elevated free SO2 showed a masking effect on TDN aroma; lower serving temperatures (11°C) enhanced TDN recognition.

Conclusions:

• Sensory thresholds for TDN in Riesling wine have been quantitatively defined.
• Free SO2 concentration and serving temperature significantly modulate the perception of TDN aroma.
• These findings offer practical insights for winemaking and service to manage or enhance specific aroma profiles.